In a luxury box high above the field at the Edward Jones Dome, the players’ father, Howie Long, will watch anxiously along with his wife, Diane, and numerous other family and friends.

Howie played 13 seasons in the NFL is a member of the Pro Football Hall of Fame. For the last 20 years, he has been one of the faces of FOX’s NFL studio coverage on Sundays. So the list of things he has not seen or experienced in his football life is a short one.

On Sunday, though, Howie will live something few in any sport ever have experienced when he watches his sons play against each other in an NFL game.

“It’s a unique week,” he told The Post.

For the first Sunday in Long’s 33 years in the NFL as a player and broadcaster, he is taking the day off so he can watch his boys play — the first time Chris, 28, and Kyle, 24, have played each other in a game at any level.

“I think we’re going to be nervous,” Howie said. “In those 33 years I think I’ve seen and done just about everything there is to do, but this isn’t in that category. This is in a whole other category.

“I don’t think any of us is really sure how we’ll feel. For Diane and me, we really don’t know how we’re going to be able to handle this. Hopefully, they both come out healthy and both play well and we’re all embracing after the game.”

The paths the two brothers took to becoming first-round draft picks in the NFL is as divergent as their personalities.

Howie described the 6-foot-3, 276-pound Chris as “an old soul.

“Chris has always had a greater appreciation for the significance of things,” Howie said.

He described Kyle as someone who was “young beyond his years.”

That explains why Chris had such a dominant career at Virginia, where his father said he was a “folk hero,” and the school retired his number before his final collegiate game.

And it explains why Kyle took more time to find himself, first playing baseball at Florida State, getting drafted by the Chicago White Sox, being taken out of school by his parents after disciplinary and academic issues, then working his way back into football as a community college walk-on, a move that got him to Oregon then drafted into the NFL.

“I think anybody who has multiple kids will tell you, ‘Same house, same love, same mom, same dad, just different kids,’ ” Howie said. “Chris, Howie Jr. and I would always laugh because Kyle was such a freak of nature. He could throw a baseball 96 [mph] in high school, run a 4.8 [40-yard dash] at 295 pounds, could jump onto a counter top.

“There wasn’t much he couldn’t do. I think that was his biggest curse: He was so good at so many things he didn’t really focus on one thing.”

Once Kyle, who is 6-foot-6, 313 pounds, found his focus, he quickly elevated his stock. Chris’ stock always was high, as evidenced by him being the second overall player chosen in the 2008 draft.

“Chris is so extremely proud of where Kyle has been and where he is now,” Howie said. “Kyle dug a hole for himself there for a couple years and not many people get out of those holes. To Kyle’s credit, he came out of the hole, checked in, showed up and has done his job.

“For the better part of a year and a half, Kyle wasn’t doing anything. He did some odd jobs, worked at a golf course, worked at a surf shop. His transportation was a skateboard.”

Howie said Kyle “decided on his own that he wanted to go back and play football,” so he walked on at Saddleback College in Mission Viejo, Calif., and said, “Hey coach, my name is Kyle, and I’d like to try out for your football team.”

Kyle played two years there then transferred to Oregon for the 2012 season before getting drafted. Now Kyle will have to block his brother on Sunday in an NFL game.

It’s difficult to imagine a prouder moment for a father than what Howie will experience. The father said he wants his boys to “take a Polaroid” in their heads to savor the moment forever.

“I’m always mindful of how the Mannings feel,” Howie said. “But Peyton is not hitting Eli. Hopefully, Chris doesn’t reduce down to [rush over] the guard a lot.”

Will there be trash talk from the two brothers?

“We’re not quite sure how they’re going to handle it or how we’re going to handle it,” Long said. “I do know, for the record, that they do love one another. There will be no ‘mama’ jokes, that’s for sure. Maybe some dad jokes.”